1. Field of The Invention
This invention relates to loading (reloading) new or used ammunition, specifically to resizing a cartridge case, trimming the cartridge case back to its original standard length, evacuating the cartridge case trimmings, and decapping the cartridge case primer pocket.
2. Discussion of Prior Art
When a round of ammunition is fired, the cartridge case undergoes plastic radial deformation (expansion). Before the cartridge case can be used again (reloaded), it must be resized in regards to its diameter. Resizing is performed by means of a resizing die mounted on the toolhead of a handloading/reloading press. The resizing die has a precisely sized steel, carbide, tungsten carbide, etc. ring, through which the fired cartridge case is inserted by means of a mechanical force exerted by the press. This resizing process causes plastic radial deformation of the cartridge case, effectively correcting the expansion from firing. However, since the mass of the cartridge case material is conserved, when the cartridge case is resized, it also undergoes axial expansion (grows in length). Over the course of firing/resizing cycles (possibly even one), the standard length dimension of the cartridge case will eventually be exceeded, therefore if the cartridge case is to be functional, sometime in the firing/resizing cycle the cartridge case must be trimmed back to its original standard length. In fact, even if the cartridge case is within functional tolerances after resizing, case to case length variations in conventional reloaded ammunition can and will cause variations in the bullets' point of impact. This variation in cartridge case length causes a variation in the bullet seating depth and the amount of bullet crimp when the case is reloaded, which leads to slight variations in pressure at firing, resulting in variations at point of impact between shots. The end result usually manifests itself in the form of vertical stringing in a group of shots.
Another detriment of cartridge case length variation manifests itself at the cartridge case expanding step in the reloading process. Before a bullet can be seated in a charged cartridge case (a case that has been resized, primed, and filled with an appropriate amount of gun powder), the mouth of the cartridge case must be expanded in order to accept the bullet. Expansion of the cartridge case mouth is performed by the insertion of a flared cylindrical tool into the case mouth to a precise depth. Due to the nature of the case mouth expanding mechanism, it can only be set-up for one exact case length. When in the process of reloading, a particular cartridge case is even slightly longer than the case used in the set-up process, then that particular cartridge case will be expanded too much, excessive coldwork (expansion) of the cartridge case material will cause cracks or splits in the case mouth and shorten the case life or even result a rupture of the cartridge case at detonation. If a particular case is shorter than the case used in the set-up process, then that particular case will not be expanded enough and it may not fully accept the bullet, resulting in a collapsed case when the bullet is seated. Both of these scenarios introduce additional variation and could potentially become dangerous. Therefore, as discussed above, it is important that cartridge cases be trimmed back to their original standard length dimension after they have been resized, in order to be reloaded.
U.S. Pat. No. 4,325,282 to Mark Schaenzer (1980) discloses a combination metal-forming/case-trimming die which can effectively resize and trim the spent cartridge case to length, however this apparatus is not motorized nor does it provide a way to evacuate the cartridge case trimmings produced by the trimming process. Cartridge case trimmings which are not removed, will work there way into the resizing section of the die, increasing the force required to fully the insert the cartridge case and damaging the exterior case wall. Other patents for cartridge case trimming include; U.S. Pat. No. 3,818,563 to Richard G. Beaulieu (1972); U.S. Pat. No. 4,686,751 to Doyle D. Gracey (1986); and U.S. Pat. No. 4,813,827 to William D. Dugger (1988); however, none of these cartridge case trimming devices are integrated into resizing or any other reloading process.
Item number RT 1200B on page 15 of the Blue Press catalog (July 1993), sold by Dillon Precision Products, Inc., sizes the cartridge case, trims the case to length via a motor driven cutter, and provides a vacuum manifold for the removal of the cartridge case trimmings. However, this apparatus requires a separate vacuum motor for the evacuation of case trimmings and due to the positioning of the motor, it will not work in conjunction with other components of a progressive reloading press. There are at least four steps (some of which are a combination of operations) that must performed on a cartridge case in order to reload it:
1. resize the cartridge case and decap the spent primer, PA0 2. reprime the primer pocket, expand case mouth, and fill with gun powder; PA0 3. manually place the bullet on the expanded case and seat the bullet; and PA0 4. crimp the cartridge case to secure the bullet in place. PA0 1. high primers, where the primer is not seated to its full depth causing a dangerous exposure of the primer side walls and risking premature detonation, PA0 2. primer seating difficulty, where a new live primer could detonate while being inserted in a used cartridge case, and PA0 3. misfires or delayed detonation, when the firing pin strikes the primer but the primer's anvil is not in direct contact with the bottom of the case primer pocket, resulting in failure to detonate or dangerous delays in primer detonation. PA0 1. to resize the cartridge case; PA0 2. to decap the spent primer; PA0 3. to clean the cartridge case primer pocket; PA0 4. to trim the case back to its precise standard length; and PA0 5. to evacuate the cartridge case trimmings.
As opposed to a conventional single-stage handloading/reloading press (which has a single-die toolhead), the toolhead of a progressive handloading/reloading press has four or more die stations, one die station for each of the above steps. Together with some additional features, a progressive handloading/reloading press can essentially perform all of the above mentioned steps with a single cycle of the press operating handle, because the cartridge cases are automatically indexed from station to station. This greatly reduces the time and effort required to reload ammunition. A single-stage handloading/reloading press requires at least one cycle of the press handle for each of the above mentioned steps, plus time to change and adjust the dies between operations. Therefore, with a progressive press performing so many operations at once, the toolhead of a progressive handloading/reloading press is cluttered. Since the motor and the large vacuum manifold of the Dillon size/trim die sit just above the toolhead, there is insufficient space for the other dies and attachments required to progressively reload ammunition. If the Dillon sizing/trimming die is used, it must be used by itself on the press and then completely removed before subsequent reloading operations can be carried out, thus defeating the purpose of the progressive reloading machine. That purpose being to reload ammunition with a single cycle of the press handle, rather than the customary four or more press handle cycles required by a conventional single-stage press (as such, the Dillon method requires two handle cycles per round). Another disadvantage to the Dillon sizing/trimming die is that it can only size/trim rifle length cases, because only this type of cartridge case extends above the toolhead, to which the sizing/trimming die is mounted. Due to the design of the Dillon apparatus (possibly based on Pat. No. 4,325,282), the trimming cutter does not extend down into the resizing die, and as such, is not able to reach the shorter pistol length cases since they are shorter than the thickness of a standard handloading/reloading press toolhead. Therefore, trimming cartridge cases can only be performed by a separate operation and thus interrupting the progressive reloading cycle.
When a round is fired, the bullet and gun powder exit the cartridge case and the only thing left in the spent case is a detonated primer, still in the cartridge case primer pocket. This spent primer must be removed (decapped) before the insertion of a live primer. As is the standard for today, decapping is usually done when the case is resized. When the cartridge case is inserted into the resizing die by means of a mechanical force, the spent primer is dislodged by a coaxially mounted decapping pin which extends from inside the upper portions of the die, through and beyond the lower portion of the die. The primer is pushed out as the decapping pin passes through the cartridge case flash hole (ignition port). However, there is a small amount of residue left in the cartridge case primer pocket. This residue should occasionally be removed. If after several firings, the primer residue is allowed to accumulate, proper seating of the primer will become infeasible. Effects of primer residue accumulation include:
U.S. Pat. No. 3,429,218 to Ole N. Olsen (1967) and U.S. Pat. No. 5,200,571 to Doyle D. Gracey (1992) disclose methods for primer pocket cleaning from hand held manual mechanisms to motorized machine held mechanisms. However, none of these mechanisms are designed in such a fashion to resize the cartridge case, trim to standard length, clean the primer pocket, and remove the case trimmings all in one step. Therefore, to clean the primer pocket of a cartridge case, the cartridge case must be taken out of the progressive reloading cycle.